Error code 6 for stage 1 random-effects TSSEM in metaSEM 0.9.6

I am trying to conduct random-effects TSSEM on a dataset of 61 studies (data set, "hamed.dat", is attached), using metaSEM 0.9.6, Openmx 2.3.1, and R 3.2.2 (2015-08-14). However, I am stuck in stage 1 of the random-effects analysis with error code "6". I even changed the default optimizer in Openmx from "SLSQP" to "NPSOL", but no luck. Regardless of changes I make to my data, it seems that I can not produce error code "0" or "1" in stage 1 of random-effects TSSEM. This is while the eigen values for the pooled correlation matrix are all positive and the matrix is actually positive definite.

So, if I use the resulted pooled correlation matrix in stage 2 of TSSEM, does it mean that for the data points with one study, the correlation will be used as a covariance toward estimating the structural model?

I am encountering the same problem. I have a smaller sample of 15 studies with a 5-variable matrix (1 binary variable, 4 continuous variables), but all 15 studies contribute data to every cell. Every study matrix is positive definite--is.pd(vector) gives TRUE for every study matrix. I get OpenMx status=6 when I run tssem1(vector, n, method="REM", RE.type="Diag"). When I rerun tssem1, I still get OpenMx status=6.

1. Within each study matrix, the correlations are sometimes based on different n due to missing data for certain variables within each study. Is this causing the problem?

2. What should I do to improve the optimization? I have run tssem1 on smaller datasets with 5 studies and similar 5-variable matrix and the first run of tssem1 gives OpenMx status=5 or 6, but after rerunning the OpenMx = 0.

3. For the 15-study dataset with tssem1 OpenMx status=6, if I run tssem2, OpenMx status=0. Can I interpret this result, and what caveats should I note given that the tssem1 had optimization problems?